In conventional embedded permanent magnet rotary electric machines, permanent magnets have been disposed inside cavities that are formed in a rotor core so as to extend in a direction of a rotational axis, insulating members have been formed so as to completely cover inner wall surfaces of the cavities, and the permanent magnets have been cooled by passing a liquid coolant through cooling flow channels that are formed by inner surfaces of the insulating members and surfaces of the permanent magnets (see Patent Literature 1, for example).
In other conventional embedded permanent magnet rotary electric machines, rotors have been constituted by an annular outer yoke portion in which permanent magnets are embedded, an annular inner yoke portion that is disposed inside the outer yoke portion, and ribs that connect together inner circumferential surfaces of the outer yoke portion and outer circumferential surfaces of the inner yoke portion, and groove portions have been formed on inner circumferential surfaces of the outer yoke portion so as to extend from a first axial end portion to a second axial end portion. The permanent magnets have been cooled by directing cooling oil that is supplied to penetrating apertures that are formed by the inner circumferential surfaces of the outer yoke portion, outer circumferential surfaces of the inner yoke portion, and the ribs into the groove portions due to centrifugal forces so as to be guided by the groove portions to flow smoothly (see Patent Literature 2, for example).